The objective of this work was to study the efficiency of nutrient utilization by Canchim (CA), Nellore (NE) and crossbreed 1/2 Canchim + 1/2 Nelore (CANE) growing heifers, in three diets: maintenance, forage:concentrate ratio (RFC) of 75:25 (test 1), diet for weight gains up to 700 g/animal/day, RFC of 60:40 (test 2) and diet for weight gains up to 1200 g/animal/day, RFC of 40:60 (test 3). Twenty-four heifers were used in each test, eight of each genetic group. Each test had by three phases: a) performance, of 90 days,where the dry matter intake and daily weight gains were determined; b) coefficients of apparent digestibility and nitrogen balance of animals; and c) liquid phase digesta passage rates. The heifers from CA, NE and CANE showed similar results, within each diet, for all analyzed variables.
nitrogen balance; cattle; performance; digestibility; passage rate; nutritive value of diet
